Solar Terrestrial Activity Report

Last major update issued on November 10, 2010 at 04:55 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)
[Solar cycles 21-24 (last update October 2, 2010)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update October 2, 2010)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update October 2, 2010)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports from January 2003 (last update October 9, 2010)]

[POES auroral activity level charts since October 2009]

Recent activity

The geomagnetic field was quiet on November 9. Solar wind speed ranged between 272 and 375 km/s.

Solar flux measured at 20h UTC on 2.8 GHz was 84.1 (up 6.0 over the last solar rotation). The planetary A index  was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.0). Three hour interval K indices: 12110000 (planetary), 02111100 (Boulder).

The background x-ray flux is at the class B1 level.

At midnight UTC the visible solar disk had 4 spotted regions.

Region 11121 was quiet and did not change significantly.
Region 11122 was quiet with some change in spot layout.

Spotted regions not numbered by NOAA/SWPC:
[S833] This region emerged early in the day in the southeast quadrant. Location at midnight: S21E30
[S834] A new region emerged early in the day in the northeast quadrant. Location at midnight: N15E51

Coronal mass ejections (CMEs)

November 7-9: No obviously Earth directed CMEs were seen in LASCO or STEREO images.

Coronal holes

Coronal hole history (since late October 2002)
Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago

A trans equatorial coronal hole (CH427) will likely rotate into an Earth facing position on November 11-12.

Image courtesy of SDO (NASA) and the AIA consortium. Annotations are my own. The darkest areas on the solar disk are likely coronal holes.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over high and upper middle latitudes is good. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be quiet on November 10-14. Quiet to unsettled conditions are possible on November 15-16 due to effects from CH427.

Coronal holes (1) Coronal mass ejections (2) M and X class flares (3)



1) Effects from a coronal hole could reach Earth within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.

Green: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability.

Active solar regions (Recent map)

Compare to the previous day's image

Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers.

Active region Date numbered Spot count Location at midnight Area Classification SDO (NASA) / AIA 4500
image
Comment
SWPC STAR SWPC STAR Current Previous
11120 2010.10.30     N41W52           plage
11121 2010.11.04 9 8 S19E07 0050 EAO BXO area: 0020
11122 2010.11.04 6 3 N14W43 0020 BXO BXO  
S833 2010.11.09   4 S21E30 0010   BXO    
S833 2010.11.09   2 N15E51 0000   BXO    
Total spot count: 15 17  
SSN: 35 57  

Monthly solar cycle data

Month Average measured solar flux International sunspot number (SIDC) Smoothed sunspot number Average ap
(3)
2000.04 184.2 125.5 120.8
cycle 23 sunspot max.
 
2000.07 202.3 170.1 119.8  
2001.12 235.1 132.2 114.6 (-0.9)  
2008.07 65.7 (SF minimum) 0.5 2.8 (-0.4)  
2008.12 69.2 0.8 1.7 (-)
sunspot minimum
3.25
2009.08 67.3 0.0 4.8 (+1.2) 5.70 / 4.89
2009.09 70.5 4.3 6.2 (+1.4) 3.88 / 3.61
2009.10 72.6 4.8 7.1 (+0.9) 3.66 / 3.56
2009.11 73.6 4.1 7.6 (+0.5) 2.45 / 2.63
2009.12 76.7 10.8 8.3 (+0.7) 1.41 / 1.92
2010.01 81.1 13.2 9.3 (+1.0) 2.93 / 3.07
2010.02 84.7 18.8 10.6 (+1.3) 4.15 / 4.61
2010.03 83.4 15.4 12.3 (+1.7) 4.58 / 4.65
2010.04 75.9 8.0 14.0 (+1.7) 10.22 / 10.24
2010.05 73.8 8.7 (15.4 predicted, +1.4) 9.18 / 8.15
2010.06 72.5 13.6 (16.8 predicted, +1.4) 8.17 / 6.85
2010.07 79.8 16.1 (18.4 predicted, +1.6) 6.31 / 5.15
2010.08 79.2 19.6 (19.6 predicted, +1.2) 8.49 / 7.77
2010.09 81.1 25.2 (20.9 predicted, +1.3) 5.33
2010.10 81.6 23.5 (23.2 predicted, +2.3) 6.07
2010.11 82.2 (1) 9.2 (2A) / 30.7 (2B) (26.2 predicted, +3.0) (2.26)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days). The official international sunspot number is typically 30-50% lower. 2B) Month average to date.
3) Running average based on the daily SWPC ap indices. Values in red are based on the official NGDC ap indices.

This report has been prepared by Jan Alvestad. It is based on analysis of data from whatever sources are available at the time the report is prepared. All time references are to the UTC day. Comments and suggestions are always welcome.